According to a recent, award-winning study conducted by The Nature Conservancy and CH2M in the wake of Hurricane Sandy, incorporating nature-based defenses into traditional infrastructure solutions provides the most effective protection against climate-related flooding.
Hurricane Sandy’s storm surge caused more than $19 billion in damages in New York City.
In the city’s Special Initiative for Rebuilding and Resiliency, planners requested a case study for one of the lowest-lying, vulnerable areas of Queens, to evaluate the role of nature and nature-based infrastructure in protecting communities from some of the impacts of climate change.
The Howard Beach Flood Risk Reduction Study and the resulting Urban Coastal Resilience Report found that a building-by-building elevation approach is not the most cost-effective way to tackle flooding challenges.
Among a variety of alternatives examined, a neighborhood-wide hybrid approach combining both nature-based features and human-made solutions proved most effective in protecting coastal areas from storm flooding.
In conjunction with sea walls and flood gates, natural infrastructure such as wetlands, marshes, mussel beds, dunes and native vegetation were found to be cost-effective in reducing the ingress of flood waters and minimizing erosion.
The study, which received a 2016 American Council of Engineering (ACEC) New York Diamond Award, makes a convincing case for investment in natural infrastructure to enhance coastal resilience and quality of life.
CH2M, which developed engineering models with detailed coastal and flooding scenarios, also worked with Tetra Tech to develop a comprehensive economic analysis. The analysis goes beyond conventional assessments, which identify costs to protect assets from flooding, to include the economic value generated by natural assets.